Moving around in the file system

Command

Action

pwd

"Print working directory" - show what dir you're in.

ls

List the contents of a dir.

ls -l

List the contents of a dir and show additional info of the files.

ls -a

List all files, including hidden files.

cd

Change directory.

cd ..

Go to the parent directory.

Examining files

Command

Action

file

Determine the type of a file.

cat

Concatenate a file.

less

View text files and paginate them if needed.

Manipulating files and directories

Command

Action

cp

Copy a file.

cp -i

Copy a file and ask before overwriting.

cp -r

Copy a directory with its contents.

mv

Move or rename a file.

mv -i

Move or rename a file and ask before overwriting.

rm

Remove a file.

rm -r

Remove a directory with its contents.

rm -i

Ask before removing a file. Good to use with the -r option.

mkdir

Make a directory.

rmdir

Remove an empty directory.

User management

useradd

Add a user. Must supply the username as an argument.

Groupadd

Adds a group. Must supply  the group name as an argument

usermod

Modifies a current user

Userdel

Removes a current user

Passwd

Sets the password. Must supply the user as an argument

Help

Man

Opens the help file. The command in question is the argument

File Permissions

ls -l

List details about the given folder tree

chmod

Changes the permission of the filename

chmod u+x filename

chmod g+rw filename

chmod g-w filename

chown

Changes the owner

chgrp

Changes the group